No, I do not plan on taking any trips outside of the US anytime soon.
I did look at the N400, but as for as I can tell it says only to list all the trips you have taken outside of the US since becoming a perminent resident and to list them on a seperate sheet of paper if necessary, it does not say anything about explaining why a trip took a longer.
I went in order to bring my grandmother, my last living grandparent, to the US. However, her healthy continued to decline and she just was not able to make the trip. I do have medical records.
I have also maintained all of my ties to the US that I had before going. I lived with my mom and dad, who are US citizens, and came back to live with them. I have continued to pay my phone bills, continued my US bank account and have paid my credit card bills. I have also served 8 yeas in the US military and am in my last year as an inactive soldier.
Thanks for your advice!